Buttonhole sewing machine



July 25, 1944.l D. B. THORNTON 2,354,559

l BUTTONHOLE SEWING MACHINE Filed Jan. a, 194s 2 sheets-sheet 1 nur...

5` I nl INVEN+DR1 BUTTONHOLE SEWING MACHINE Filed Jan. 8,- 1945 2 Sheets-Sheet 2 I E 1Q-E 22, 2/ L l INvrN'l-ER Teuf;

by TQLSuGJM .Q45

f ,AH-ys- Patented July 25, 1944 L PATENT?- OFFCE" .David B. Thornton, West Newton,'Mass., assignor to The Reece Button Hole vMachine Company,- Boston, Mass., a. corporationy of Maine applicati@ January 8, 1943 seria1Nu 471,541

1 A 11 Claims. Thisinvention relates tosewing machines and especially to buttonhole. sewing.A machines ofthe type .known as straight hole machines, 'de-.

1 Theinvention relatesparticularly. yto athread pickf-upgdevice whichj engages the thread between the work and the. needle after the :thread has been cut or 'trimmed and ypulls the Aloose end of thread out. ,of theworkand. holds it out of the pathof the clampingimechanism and needle until 4the rstgstitch has been formedjin the next sewing operation. .The object` of@ the ypresent invention is to remove and'hold the ,trimmed thread as aforesaid very. quicklyduring .the brief interval after the trimming voperation :and before the` machine comes to. rest at the end of a sewing operation. Buttonhole sewing machines of the straight holef' typeto which this invention relates includeV a cutter for cutting the buttonhole slit substantially upon the completion of the stitching operation, usually during `thejfor'mation of they last stitch, and 'a thread trimmer timed to operate immediately thereafter upon the completion of thelast stitch to sever 'or trim the thread below the Work. Trimming is, therefore, the last operation performed before 4the machine comes to rest, and; as will later appear, takes place simultaneouslywith the operation of the stopping "'mechanism'. In* such machines, the thread pickup mechanism must operate in the very short period `of timeafter the riseof the needle duringthe completion ofthe 1ast`sttch,

and after the lthread. trimming cutter has cut the thread, but before the machine'comes fully torest. l

` The Ainventionfwill best be` understood from the following description of an illustrative 'embodiment thereof sh'own in the accompanying drawings;

In the drawings: I' j Fig; 1 isa viewiii side elevation, partly brokenV away, of a machine embodying thepresent in-V vention; Fig. 2 is a view along hne 2-2 of Fig'l;"

Fig., 3 is a View of a portion of the machine as seen from the right in Fig. 1j

Fig. 4 is a view of a portion of the left sidey of" said machine, showing mechanism embodying the? present invention' in :one operative position.I

5 is a similar View of thersamemechanism in a diiferent operative-position; y y

Fig, 6 is'a view alongtheline 6 5 of Fig. -5; and

Fig. 7 is a. detail view of the pull-off device of the present inventiom.- A j The machine shown in the drawings'may, as to itsgeneral. organization, be similar4 to those described in the patents above referred to. Y.It comprises a bed I5-fromrwhich rises av standard llfcarrying anoverhanging arm I'l spaced above thebed. The work W is carried by a work clamp orholder comprising a clamp plate I8 and cooperating clamping arms I9 havingv clamp feet; I2.

The stitch formingl instrumentalities comprise an eye pointedfneedlezll above the work and co-` operating loopers or under .threadhandling devices 2ly below the work.` -The needle 20 is carried by a needlebar 2.3 which is vertically reciprocat'edby Vmeans generally-indicated at 24 in a. needle bar guide25. "'Ihe'thread t passes from a suitable source .(not shown) through a take-up 26 and suitable tension devices 2lA andv 23 to the needle eye, whence it passes through the work W and a throat plate 22 ,tothe loopers 2l.

The stitch'forming instrumentalitiesare driven by'a main shaft 29'journalled insuitable bearings in thebed I5. Said shaft has power applied thereto by a belt 30 alternatively engageable with fastand loosel pulleys 3Ifand 32 under control of a belt shifter 33. The belt shifter 33 constitutes an extension of a stop member or arm 34 carried cam 44 fast onv the shaft 29 This cam has a.

concentric portion a, a rise b, a notch c and a stop shoulder d arranged to; engage the nose 43 inV rthe order named when .the shaft 29 is rotatedin the vdirection of the arrow inFig. 3. A spring. pressed-plunger 45 carried by the upright I6 'engages the stop arm 34 and tends to turn .Ls'aid armand the rock shaft35in a clockwise direc?.

tin, ,3S ShOWll in Fig.,- 3. to press Ythe n'ose:4i3`

against the peripherygofv the cam 44 when ,saidv nose is in the path of movement of said cam. The buttonhole Vcutter A5l) is carried bya' lever 5I journalled on a short stud shaft 52supported in the. bed l5, said lever having an 'arm 53 carnalled a stud 55 having at one end a sleeve portion 56 which receives a stud 51 extended inwardlyfrom the stop arm 34.

During the formation of the last stitch, the 5 machine runs under its own momentum and the nose 43 follows the periphery of the cam 44. As said nose is engagedby the rise b of said cam, the stop arm 34 isv lifted against "the action of the spring-pressed plunger 45 into the position l0 shown in Fig. 3. This lifting of the stop arm gf .a in Fig. 4 by a spring 84 into a position deter- 34 operates, through the stud 51 and its connection with the arm 53 of the lever 5|, to depress the buttonhole cutter 59 and cause the same to y cut the buttonhole slit. The reafter,` the nose 43. 15

drops off the rise b of the cam 44 and entersthe Y notch c, under the influence ofthe spring-pressed plunger 45, this movement causing the buttorr^" hole cutter 50 to be raised to its original position.

The construction, arrangement and mode of 20 operation *of the parts above referred toA and certain associated 4parts are orfmay be substanytially kvas more fully described inthe above mentoned patents. `A'stitch-setting and thread trimming element 25 58 is guided in ways in the-bed I5 immediately f below vthe throatplate 22. The element 58'irec'eives a stud 59 carried by an armll fast on one" end of a rock shaft 6| journalled in 'suitable bearingsm the bed 15 and having Seeuredto its ope? au posite end'an arm 62 which is pivotally connectedV to'aA4 link 63 guided'on the outer lsideV of thebed ona screw-64 projectingfrom the bed and'rel" ceived Ain Ya sl'ot`65" in said link.L The opposite endof the link 63 is formed with 'a'notch E6 35- adapted to be entered by a nose 61 on ay collarl 88 secured to the stop boltA 4|. f

present invention. They are, or maybe, sub 50T stantially' [like lthe 'mechanism described 'and claimed in a copending application 'of Joseph H. j Pikul, SerialNo. 401,932,1iled July 11,' 1941.

Since` they movement AVof the' nose 61 into 'the notch |55 occurswhen the `stop member 34 isf moved ydownwardly andl the'nose `43 enters the notch-ic, and since this movement coincides with the* raising ofV4 the buttonhole' cutter lever 5| through the `mechanismdescribed above, the

trimming operationv takes place practically's`ij" Gv multaneously withf'the return of the button h o'le'' cutter to its raised,inoperative position.v In the present invention, -a thread pick-up device is used to pull thev vthread-outer the `work" andahold itin a positionin which it will not be' 655 caught by theA clamp feet when the clamp `4isJ closed 4at thebeginning of the next sewing op-VVA eration. Y A '1 1 l The zpick-up device comprises a hook 1li-'formed' at onel end of a curved arm 1| having an in-'f 7W turnedend 12 adjustable connected to the'arrn'v 1.3 of :a .levery 14and held 'against'movement, therein except during adjustment by a screw `1-5. The arm `1| iscurved in suchv manner-as to ex' tend outwardlyand downwardly JfromV the arm'fisf` 13 (Fig. 7) to terminate in the straight shank 16 of the hook 18. The shank 16 is provided with a friction piece 11 of felt or similar material which extends into the angle of the hook 10. The lever 14 is pivoted at 18 to the needle bar guide 25 and normally urged outwardly and against an adjustable stop 80 by a spring 19. The other/arm 8| of the leverv 14 extends rearwardly into ,the pathof ,movement of a pawl 82 pivoted at 83 on the button hole cutter lever 5| and normally urged in a clockwise direction as viewed mined by'engagement of a stop screw 85 in an extension 860i saidpawl 82 with a shoulder 81 formed' Aon said lever 5 I.

At the end of asewing cycle, when the needle 20 rises in the formation of the last stitch, and

the automaticv stopj mechanism of said machine comes into operation, the stop arm 34 is lifted as hereinbefore described into the position shown inlvig.l 3, andoperates, through the stud 51 and its connectiomwith.the-armv 53 of the lever 5|,l

tofdepress the button hole cutter 50 tocut thev button hole slit. As'the button hole 'lever 5| lis depressed, the pawl'82is brought into contact with the-'end of the-S arm .8| lof the lever 14- and is rotated 4counter-clockwise inY Fig. v4 against the impulse of the spring 84 until itpasses be#A yond the arm 8|, thereby permitting .said pawlfto pass the arm 8| idlyduring the downward move-'- ment .of the cutter 50. After the pawl has passedf by the arm. 8|, theispring 84 causes it to move clockwise .to .reassume its normal position.

After the cutter 50 has cut the buttonhole slit in the work W, the nose 43 drops into` the notch c in the cam 44, allowing the stop arm 34'to be depressed by the spring pressed plnnger45, causing the. lever 5|y to be raised to its'original posi-1 tion as shown in Fig. 1. At this time thel stitchsetting and thread-trimming element .58 sets they lastf stitch andcuts the threadbelowv the work. Then. as--the lever 5| risesas, aforesaid, .the top between the needle andthe'work as Shown in full lines 4in 5. The continued upward move- 1 mentofthearm 5| thereafter carries the pawl-E 82 out of contact V with the arm 8|, whereupon the, spring l19 causesthe lever 14 to rotateina coun;v ter-clockwise hirection into the position shown in Fig. 4 andjinjbroken lines in Fig. 5 to swing the curved ar'mil outwardly and upwardly. As the' arm 'swings out, the thread is caught in the angle of the vhokan'd held there by the frictionf piece 11. Continued. outward movement .of the' arm 1| servesY to pull'the' trimmed end of thread out of .the work, the arm 1| finally coming Ato rest in {thread-holding position as shown inFig. 4, in which the thread is held'away 'from the work clamp. At the beginning of the'next sewing operation the work clamp is closed upon .thework' tion; stitch-forming mechanism including a` needle carrying a needle thread, "a lever carrying a Vlmttonhole cutter, means for moving said lever alternately in'opposite directions 'to vcause saidV cutterto 'c'uta'lbuttonhole slitandthen retract'l needle pulling the thread' out the same, a'pick-upifortlreneedleA thread, and means carried4 by lsaid-@lever foril -engagiiigl vandoperating said pick-up, said operating means idlyv passing saidpick-'u'p duringlfthe' cutting movement 'of `'said lever but acting-during the retract-l ing movement thereof to cans'emovement of'sai'd pick-up first' into thread receiving position-and then into thread pick-up-'pos'ition` 2. In a buttonholefsevvingfmachine,"in-combination, stitch-forming mechanismincludingja needle vcarrying aneedle,V thread; means -for conel trolling said mechanism ft'o' cause the. 'saineitc perform a predetermined` series of*stitch''formi'n''g-` operatinsv and stop, la lever jcarryin'gya button-l" hole cutter, means -for moving vsaid"lever 'alternately in oppositeA directions Ato cai-irseE said `clutter' to cut a buttonhole slit during' the latter part-:fi the finalvstitch-formingbperation andthen re-'n tract the same,'a pick-,upffor the-needle threadj and means carried'b'y' said lever for engaging! and operating said prickup, said operating means idly passing said pick-up during the cutting movement of said lever but acting during the retracting movement thereof to cause movement of said pick-up first into thread receiving position and then into thread pick-up position.

3. In a buttonhole sewing machine, in combination, stitch-forming mechanism including a needle carrying a needle thread, a lever carrying a buttonhole cutter, means for moving said lever alternately in opposite directions to cause said cutter to cut a buttonhole slit and then retract the same, a pivoted pick-up for the needle thread, a spring for normally moving said pick-up into thread pick-up position, and a spring-pressed pawl carried by said lever in a position to engage said pick-up when said lever is moved as aforesaid, said paWl being so disposed on said lever as to pass said pick-up idly during the cutting movement of said lever but, during the retracting movement of said lever. to move said pick-up into thread receiving position and then release the same and permit said spring to restore it to thread pick-up position.

4. In a buttonhole sewing machine of the type having stitch-forming mechanism including a needle carrying a needle thread, and a stop mechanism that operates to stop the machine upon the completion of a predetermined series of stitchforming operations by said stitch-forming mechanism, in combination, a buttonhole cutter, means to operate said cutterto cut a buttonhole slit during the latter part of the iinal stitch-forming operation and then retract the same, a pick-up for the needle thread, and means rendered operative by and during the retracting movement of said buttonhole cutterv for moving said pick-up rst into thread receiving position and then into thread pick-up position.

5. Ina buttonhole sewing machine ofthe type having stitch-forming mechanism including a needle carrying a needle thread, and a stop mechanism that operates to stop the machine upon the completion of a predetermined series of stitchforming operations by said stitch-forming mechanism, in combination, a thread trimmer, means for operating said trimmer to sever the needle thread substantially coincidentally with the stopping of the machine, a buttonhole cutter, means to operate said cutter to cut a buttonhole slit during the latter part of the iinal stitch-forming operation and then retract the same, a pick-up for the needle thread and means rendered operative by and during the retracting movement of said into thread. receiving. position and :thenl into.' thread pick-upposition. Y i -f-,va-

6. In a buttonhole sewing machine 4vof the .type having stitch-forming. mechanism .includinga needle carrying a needle thread, and a stop mechanism that operates to stop the machine upon` the completion of a predetermined series Yof stitch-.. forming operations by said .stitch-formingvmech-f anism, said needle rhavinga work;penetrating movement and a retracting movement duringleach stitch-forming operation, combination,V a :but-- tonhole cutter, means to operate said vcutter to out a buttonhole slit during. the; needle retracting movement of the nal stitch-forming operation and then retract the same, 1a pick-upyforatheneedle thread, and means rendered operativeby and during the retracting'r'novement of'isaidbut-f. tonhole cutter for'movings'aid pick-up rst intol thread receiving position and then into thread y pick-upposition. l. Y

7. In a buttonhole sewingimachine of-ther-type having stitch-forming mechanism .including a needle carrying a needle thread, and a stop mechanism that operates to stop the machine upon the completion of a predetermined series of ,stitchforming operations by said stitch-forming mechanism, in combination, a thread trimmer, means for operating said trimmer to sever the needle thread substantially coincidentally with the stopping of the machine, a buttonhole cutter, means for advancing said cutter to cut a buttonhole slit during the latter part of the final stitch forming operation and for retracting said cutter after said slit has been cut,a thread pick-up member, and means rendered operative by and during the retracting movement of said buttonhole cutter for moving said pick-up member into thread receiving position and for moving said member into thread pick-up position when said trimmer has severed the thread.

8. In a buttonhole sewing machine of the type having stitch-forming mechanism including a needle carrying a needle thread, and a stop mechanism that operates to stop the machine upon the completion of a predetermined series of stitchforming operations by said stitch-forming mechanism, in combination, a buttonhole cutter, means operated and controlled -by the stop mechanism for operating said cutter'to cut a buttonhole slit immediately prior to thestopping of the machine and during the latter part of the final stitchforming operation and then retracting the same.

a pick-up for the needle thread, and means rendered operative by and during the retracting movement of said buttonhole cutter for moving said pick-up rst into thread receiving position and then into thread pick-up position.

9. In a buttonhole sewing machine of the type having stitch-forming mechanism including a needle carrying a needle thread, and a stop mechanism that operates to stop the machine upon the completion of a predetermined series of stitchforming operations by said stitch-forming mechvanisms, in combination, a thread trimmer, means operated by the stop mechanism for operating said trimmer to sever the needle thread substantially coincidentally with the stopping of the machine, a

buttonhole cutter, means also operated by said stop mechanism for operating said cutter to cut a buttonhole slit immediately prior to the stopping of the machine and during the latter part of the nal stitch forming operation and then retracting the same, a pick-up for the needle thread, and means rendered operative by and buttonhole cutter for moving said pick-up first lliV during the retracting movement of said buttonhole cutter vfor movingrsaid pickfup 'rst into' thread receiving position.andz-then-pinto thread pick-up position. i f

' 10.I In a, lbuttonhole sewing machinelof. the -type having stitch-forming mechanism including aA needlecarrying a needle thread, and a stop mech,

`machine of the type having. stitch-,forming mechanism including auneedle carrying a needle thread, and a stop mechanism that operates to .stop the machine upon the completion of ya predetermined series of stitch-forming operations by said stitch-forming mechanism, said needle having a work penetrating movement anda retracting movement during each stitch-forming operation, in combination, a .thread trimmer, means for operating said trimmer-tosever the needle thread substantially coincidentally wththe stopping of the machine, a'lpick-up for theneedle Vthread movable into thread reeivingjand thread pick-up positions, meansten'ding normally to move said pick-up into thread Apiclfgup position, and means for moving saidvpick-up into thread receiving position during vthe needleretracting movement of the nal stitch` vforming operation and for thereafter releasing the Vsame to permitl it to move into thread pick-up position when the thread has been severed. y i' DAVID B. THORNTON. 

